Herbicidal compositions



Patented May 5, 1953 LNpDrawing.-.Applicatioii'LJanuaryJM;1952, "Serial. No. 268,140

11 iTheipresent inventionsprovides new and-"highly waluable herbicidal ,1 v eompcsi-tiens and -'--methods of destroyingsoripreventingplantgrowthin which zsaid.compositions are 'employed.

'2 The present invention is" further illustrated, but not limited, by the following examples:

Example.- .1

1;]: ih m 'yf nd th b 'im -i t 5 Spray testing Of theepresent he1'bicidal-,;comenema-ea compositionsare-:obt'ained when'there Positions conducted-es *fOHOWSI are prepareaioinin wateeemuisionsvor zwinyp eiclohexenwe solution'ofr Minylmercaptof,z m?3r cap1;db'efizgbhjazal benzcthiazole together with ankemulsifying agent .ifii-leliblfilfial compositions:containing the 'thialies'eddedioWater;eheiquemiiy ofeolufiofiemrxzoles are'"readily obtained by first 'prepar ineua 1o'Fpleyed'ibeing Yeeleuieteddoi'give"femllieinne*con solution of the comp'ound i tan-organic solvent taming nd 1.0% :of i the: th-iazole sriandlthenfiaddin the-resulting soluticn to water (GOmPOmi l'eepeetivelywbeeed"'efii'the "Weigheof acontainingeran ci mmsfiy [agent g an the totale'mulsion.iThenuantityotemulsifying eiem-ulsion. 'eeause of the'very"high herbicidal ed Was by w htxbasedon the deficienc iyi-n'ylme icaptgbenzgthi'gzdle;2itji "eweightof the. total emulsion. Said emulsifying presentLdh )the-;he,1tbicida,1 composition in only "agentcomprisedwa mixture ofla polya-lltyleneglycol very small concentrations, for example, in con- "rdeliiv'etivefind ybe e'sul'fonate. centrations -i 1 weight of the mThree-weekavold corneand-be'an plants," respectotal weight of the emulsion. Emulsifying agents were Sprayed With the emulsions, two which may be employed are those customarily ts of each variety being employed. The used in the art for the preparation of oil-in-water spraying was continued until droplets formedon emulsions. The word oil is here used to desfell from the foliage and stems of the ignate any liquid which is insoluble in water. Sprayed Plants, up to 15 of the emulsion being Examples of emulsifying agents which may applied to each Plent- The Sprayed Plants as be used include alkylbenzenesulfonates, long Well as two eated blank specimens of chained polyalkylene glycols long chained each plant were then allowed to remain under i t t The emulsions may be used to standard conditions of sunlight and watering stroy already existing m m; growth by direct for a period of one week. At the end of that time application to the undesirable plants, e. g., by the sprayed plants Were compared With the p ayi g; or the emulsions may be employed t treated plants in order to determine the extent prevent, plant, growth by appucafion to media of injury, if any. The following observations which normally support plant growth. When were made? employed to prevent plant growth, for example in parking areas, highway abutments, railway Concentration of 2- Efiect0n yards, etc., the emulsions may be applied by g'grggggg g g gg spraying only the surface of said media or they emulsion Bean Corn may be admixed with said media. Generally, spraying of only the soil surface is sufiicient 0.1% Moderate injury Moderate injury. to prevent plant growth in areas which are gfgg gigw leaves Plant dead to be kept clear of plants. However the emulsions 40 .0% Plant dead, leaves Plant dead, leaves may be incorporated into customarily employed dmpped' temporary surfacing materials, e. g., soils, cinders, em Example 2 Th present il-int emulsions of 2- 'm 1- Another method of testing for herbicidal effimercaptobenzothiazole are particularly valuable 5 of Chemical V l e nOting t effects in that when applied to the leaves of broad-leafed on d e on a d plant owth which plants they cause leaf-drop. Application of the y be evidenced y p y $011 Surfacess present herbicidal compositions to such plants test, o y nown as Dre-Emergence st as cotton, beans, and peas defoliates the plants W s Co ducted as follows: and thus permits more efficient harvesting or BOXES having a X exposed a were hand-picking of the bolls or pods.

partially filled with a layer of soil and 20 seeds 3 were placed thereon and then covered with /4" to layer of soil which had been screened to A sieve. Test boxes containing 20 seeds each of rye grass and beet seeds, respectively, were prepared. The surface soil of the seeded boxes was then sprayed, respectively, with the 1.0 per cent and the 0.3 percent emulsions of Example 1. The quantity of each emulsion which was applied was calculated to correspond to either 20 lbs. of the sulfide per acre or to 50 lbs. per acre. In the present instance, 10.8 cc. of the 0.3 per cent emulsion per 25 square inches of surface soil was calculated to correspond to 20 lbs. of the chemical per acre and 9.1 cc. of the 1.0 per cent emulsion to 50 lbs. of the chemical per acre. The sprayed boxes as well as similar seeded but unsprayed boxes were then maintained at standard conditions of temperature and watering for a period of two weeks. At the end of that time the number of healthy seedlings in each box was counted. Thus the number of nonemerging and damaged seedlings was obtained by difference. This diiference is designated as X. phytotoxicity was determined by the ratio of 5' X to the number of healthy seedlings in the controls.-

There was evidenced a 71-100% phytotoxicity to both test specimens at the 50 lbs/acre rate "of application. At the 20 lbs. rate there was evidenced a phytotoxicity of up to 70% against "rye grass and a phytotoxicity of up to about 45% against beets.

While the 2-vinylmercaptobenzothiazole is most advantageously employed as a herbicide by plant growth. The thiazole may also be mixed Per cent 4 with liquid or solid agricultural pesticides, e. g., insecticides and fungicides. While solutions of the compound in organic solvents may be employed for preventing and destroying plantgrowth, I have found that the emulsions possess an improved tendency to adhere to the treated surfaces and that less of the active ingredient, i. e., the 2-viny1mercaptobenzothiazole, is required to give comparable herbicidal efliciency.

What I claim is:

'1. A herbicidal composition comprising an oilin-water emulsion of 2-vinylmercaptobenzothiazole, said thiazole being present in said emulsion in a quantity which is toxic to plant life.

2. The method of destroying undesirable plants which comprises applying to said plants a toxic quantity of a herbicidal composition comprising 2-vinylmercaptobenzothiazole.

3. The method of destroying undesirable plants which comprises applying to said plants a toxic quantity of a herbicidal composition comprising an oil-in-water emulsion of 2-vinylmercaptobenzothiazole.

4. The method of preventing plant growth which comprises applying to media normally supporting said growth a herbicidal composition comprising 2-vinylmercaptobenzothiazole.

5. The method of preventing plant growth which comprises applying to soil normally supporting said growth a herbicidal composition comprising 2-vinylmercaptobenzothiazole.

6. The method of preventing plant growth which comprises applying to soil normally supporting said growth an oil-in-water emulsion of 2-vinylmercaptobenzothiazole.

7. The method of defoliating plants which comprises applying to the foliage of said plants a herbicidal composition comprising an oil-inwater emulsion of 2-vinylmercaptobenzothiazole.

MILTON KOSMIN.

No references cited. 

1. A HERBICIDAL COMPOSITION COMPRISING AN OILIN-WATER EMULSION OF 2-VINYLMERCAPTOBENZOTHIAZOLE, SAID THIAZOLE BEING PRESENT IN SAID EMULSION IN A QUANTITY WHICH IS TOXIC TO PLANT LIFE. 